In a vehicle, in particular in an automatic transmission of a vehicle, a multitude of assemblies is installed, which assemblies are operated with the assistance of a pressure medium-actuated actuator, in particular with the assistance of a hydraulically actuated cylinder, in order to transfer the same between an unactuated position and an actuated position. Thereby, under the state of the art, two redundant pressure medium valves are provided for controlling the pressure medium-actuated actuator, whereas the pressure medium-actuated actuator can be transferred from an unactuated position to an actuated position only if, in each case, the pressure medium valves occupy a pressure supply position. Thereby, the operational reliability in the operation of such an assembly of a vehicle can be increased.
If there is an undetected error at one of the redundant pressure medium valves, for example by the fact that the pressure medium valve is stuck in the pressure supply position, despite the redundant design of the pressure medium valves, a critical state may arise due to a simple error at the other pressure medium valve in combination with the undetected error that is already present; i.e., because of the fact that the assembly unintentionally occupies an actuated position. As such, there is a need to subject the redundant pressure medium valves to a functional test, in order to examine whether there is an undetected error at the pressure medium valves.